Self-operating evaporative cooler



June 24, 1952 w. c. DE WlTT SELF-OPERATING EVAPORATIVE COOLER Filed May 22. 1951 WIENTOQ 25x) &

Patented June 24, 1952 UNITED STATES PATENT OFFICE SELF-OPERATING EVAPORATIVE COOLER William 0. De Witt, San Bernardino, Calif. Application May 22, 1951, Serial No. 227,047

5 Claims. 1

Thisinvention relates to self-operating coolers.

One of the objects of the invention is to provide a self-operatingrevolving wheel which will dip a series of tubes having evaporating surfaces beneath the surface of water contained in an open trough "and carry these tubes through the air to evaporate 'water from said evaporating surfaces, and in this waycoolthe air passing over said surfaces and the surfaces themselves.

A second object is to provide a self-operating evaporating'wheel,consisting of 'a circular tubular rim element supported on ahub anda shaft having laterally extending evaporating tubes connected'to said rim, closed at their outer ends, and angularly disposed relative to the diametrical plane of the rim forming a substantially cylindrical structure, said rim and said tubes beingpartially filled with a volatile liquid, and said wheel being journalled so thatthelowerportionof said cylindrical structure will run through a trough containing water to be evaporated, so that heat absorbed from said Water will evaporate said volatile liquid and cause the vapor thereof to ascendto the upper part ofthe cylindrical structure whereit will be cooled and liqui'fled by evaporation of water on the outside-of said 'tubesand will betrapped-in tubes on one side only of said cylindrical structure, thus causing said wheel to rotate;

Another object is to provide an evaporative wheel consistingof a cylindrical shaped tubular structure journalled to rotate so that the lower segmental portion willdip into waterand become moistened, so that as the wheel rotates, this upper moistened portion will be exposed to the atmosphere and evaporation of wateron said portion will cool it; the interior of said structure being partially filled with a volatile liquid and shaped so that when the vapor of said volatile liquid condensesin the upper part ofsaid tubular structure, it will be trapped in receivingcontainerson one sideof said structure only so 'thatsaid wheel will be unbalanced and will rotate.

Other objects will appear hereinafter.

Figure l is an end view of one form-of my'wheel type evaporative cooler; 0

Figure 2 is a side view thereof, with certain parts shown in section taken on line "2-2 of Figure 1;

Figure 3 is a .plan view of the water tank through which the lower portion of the wheel turns, with other parts sectioned off-substantially on line '3-3 in Figurez;

Figure 4 is a plan view of afragment of the wheel structure 'drawn on an enlarged scale;

Figure 5 is a side elevation of aportion of modified form of wheel structure and Figure 6, an end view of a fragment of said modified form of wheel.

Similar numerals refer to similar parts in the several views.

The wheel 2 has a hollow circular rim 3 which is supported by spokes 4 extending from. hub 5. The hub is keyed to shaft 6 which is journalled in bearings 1 on supporting frame 8. The two end portions of frame 8 are supported on the sides of tank It]. The tankispositioned-beneath the wheel so that a segmental iportion l2 of the rim 3 clips into and runs beneath the surface of Water M in the tank.

The hollow rim 3 is, in the form of the device here illustrated, tubular and the evaporating and vapor collecting tubes 15 extend laterally from each of its sides. These tubes are all slanted angularly relative to the plane of the diameter of the rim, but in extending outward the tubes conform substantially to the size and annulus of the rim and thus form a composite wheel structure of substantially cylindrical shape. The tubes on the leftside of rim 3 (indicated by letter B) extend laterally outward and angularly upward and those on the rightside (indicated by letter A) extend laterally outward and angularly downward. The result of this construction gives the side elevational view of wheel somewhat of a herringbone appearance. The outer ends of all tubes l5 are closed. The rim 3 and the tubes I5 are preferably made of copper and all joints and seams are welded or brazed.

The interior of the rim 3 and tubes I5 is filled about one-fourth full of a volatile liquid, such as methyl chloride or Freon.

To retain more moisture in contact with tubes l5, theymaybe covered with fabric 11, as shown in Figure 4.

The entire wheel ma be placed ina wind tunnel or duct 22, indicated byolotted outline, Figure 3, or heat transfer tubes'23 placed in tank I 0 and used to convey and circulate a liquid to be cooled. Liquid flowing through tubes .23 is in thermal transfer relation to thewater M in the tank, but out of contact therewith.

The modified form of evaporating wheel shown in Figures 5 and 6 has two rim rings 30, supported on spokes 4 and shaft 6, between which evaporating tubes .25 extend. These tubes are bent in the middle so thateach of theirend portions is angularly disposed relative to thediametrical plane of each ring. 0

In operation, rotationof the wheel is started densation of the vapor of said volatile-liquid in the upper part of the wheel and its entrapment in the outer end portions of downward and laterally extending tubes on side A of the wheel. It is to be noted that vapor will condense near the top of the wheel and run to the outer portions of these tubes where it will remain until these tubes are immersed in water I4 in tank l0, and absorb heat therefrom. 7 On the other hand, since tubes [5 on side B slant downward, any liquid collecting in them will drain back into rim 3, and they will retain no liquid. The condensed liquid in the tubes on side A will, therefore, make this side heavier and unbalance the wheel su'fficient to maintain rotation in the direction indicated.

Bafiies direct and distribute flow of water I4 in tank ll].

In the modified form of wheel shown in Figures 5 and 6, condensed vapor is collected at the central bend 33 of each of tubes 25.

In either case the condensed vapor within the wheel is entrapped by the evaporating tubes on side A of the wheel, while any vapor condensing on side B flows back into the hollow rim 3 or rims 30 and flows to the bottom of the rim structure. The tubes on sideA act as traps to catch and retain down flowing condensate, while the tubes on side B by-pass the condensate and do not trap it.

Since the surface of tubes l5 or 25 are moistened after they leave tank I0, and evaporate this moisture as the wheel rim travels through the upper portion of its orbit, refrigeration is produced by the evaporation of the moisture. This refrigeration cools the air surrounding the wheel so that if it is placed in a win-d tunnel or duct 22 it will cool air all through the tunnel over the surface of the wheel. Part of the refriger ation (cooling due to evaporation) is absorbed by the metal structure of the wheel. Since copper is conductive of heat the whole wheel structure becomes cooled. This cooling or refrigeration is, in turn, transmitted to water I4 in tank l0 and can be used to absorb heat from fluid in pipes 25.

In any case the wheel operates without the need of power to turn it, and if installed to take the place of a cooling tower, eliminates the need for power to pump water up into the tower. If used to cool and humidify air passing through a duct into a building, it eliminates the need for power necessary to turn an evaporating pad wheel or drum, or to pump and spray water onto any such pad.

While I have shown but one preferred form of the device and one modification, many other modifications are possible, many other uses, including the generation of power, may be made of the device. In view of the foregoing, I make the following claims.

I claim: 7

1. A self-operating refrigeration evaporating wheel comprising a wheel structure having a hol- 4 low rim of heat conductive metal supported on a horizontal shaft, a plurality of evaporating tubes of heat conductive metal attached to the sides of said rim and opening into its interior disposed angularly relative to the diametrical plane of said wheel and closed at their end so as to trap condensed vapor within said rim on one side of said rim, a volatile liquid within said wheel structure filling the lower portion thereof, a tank containing water disposed below said wheel .structure so that the lower portion of the wheel will dip into said water as the wheel rotates, and means including flow directing ducts for bringing fluid substances to be cooled in heat transfer relation with the surfaces of said rim structure. 2. A self-operating evaporating wheel for producing refrigeration by evaporation of water comprising a cylindrical hollow rim structure, of heat conductive metal mounted on a horizontal axle, a plurality of tubes spaced around said rim structure opening into the interior thereof and extending laterally therefrom saidtubes being disposed at substantially uniform angles relative to the diametrical plane of said rim structure and closed so as to provide condensate collecting pockets adapted to collect condense vapor on one side of said rim structure; a volatile liquid in the interior of said hollow cylindrical rim structure and tubes filling a segmental portion at the bottom thereof, and a tank containing water to be evaporated disposed so that the lower segmental portion of said cylindrical rim structure dips beneath the surface of said water.

3. A self-operating evaporating wheel for producing refrigeration by the evaporation of water, including in combination, a hollow cylindrical rim structure of heat conductive substance mounted to rotate on a horizontally positioned axle, condensate pockets formed on said rim and adapted to trap vapor condensing in the upper portion of the interior thereof on one side of said rim structure, volatile liquid filling a lower segmental portion of the interior of said rim structure, and a tank disposed beneath said rim structure containing water to be evaporated at a level such that a segmental lower portion of said rim structure will dip beneath the surface thereof.

4. A self-operating evaporating wheel for producing refrigeration by the evaporation of water, including in combination, a hollow cylindrical rim structure of heat conductive substance mounted to rotate on a horizontally positioned axle, condensate pockets formed on said rim and adapted to trap vapor condensing in the upper portion of the interior thereof on one side of said rim structure, volatile liquid filling a lower segmental portion of the interior of said rim structure, and a tank containing water to be evaporated disposed beneath said rim structure, said water being at a level suflicient to immerse said lower segmental portion of said rim structure containing said volatile liquid so as to be in heat transfer relation thereto.

5. A self-operating evaporating wheel for producing refrigeration by the evaporation of water from the surface thereof, comprising in combination, a cylindrical hollow rim of heat conductive material mounted to rotate axially on a hori zontal shaft, a plurality of spaced evaporating tubes of heat conductive material extending outward from the sides of said rim, and opening into the interior of said rim, said tubes being closed at their outer ends, and directed angularly relative to the diametrical plane of said rim so as to form traps to collect liquid formed from the condensation of vapor in the upper portion 0! the interior of said rim on one side of the annulus of said rim, fabric covering the exterior of said tubes to enhance evaporation of water therefrom, a volatile liquid within said rim filling a segmental lower portion thereof, a tank disposed beneath said rim containing water to be evaporated at a level suflicient to immerse a lower segmental portion of said rim and said tubes thereon so as to be in thermal transfer relation to said volatile liquid within said rim, and tubes in the lower portion of said tank adapted to circulate a liquid to be cooled through the water in said tank in thermal transfer relation but out of contact with said water.

WILLIAM C. DE WITT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 10 Number Name Date 2,288,981 Viebrock July 7, 1942 2,499,411 Pennington Mar. 7, 1950 2,524,697 Epperly Oct. 3, 1950 

